linux/drivers/gpu/drm/lima/lima_gem.c
Thomas Zimmermann 0cf2ef46c6 drm/shmem-helper: Use cached mappings by default
SHMEM-buffer backing storage is allocated from system memory; which is
typically cachable. The default mode for SHMEM objects is writecombine
though.

Unify SHMEM semantics by defaulting to cached mappings. The exception
is pages imported via dma-buf. DMA memory is usually not cached.

DRM drivers that require write-combined mappings set the map_wc flag
in struct drm_gem_shmem_object to true. This currently affects lima,
panfrost and v3d.

The drivers mgag200, udl, virtio and vkms continue to use default
shmem mappings.

The drivers cirrus and gm12u320 change caching flags. Both used
writecombine and now switch over to shmem defaults. Both drivers use
SHMEM objects as shadow buffers for internal video memory, so cached
mappings will not affect them negatively.

v3:
	* set value of shmem pointer before dereferencing it in
	  __drm_gem_shmem_create() (Dan, kernel test robot)
v2:
	* recreate patch on top of latest SHMEM helpers
	* update lima, panfrost, v3d to select writecombine (Daniel, Rob)

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Maxime Ripard <mripard@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20201117133156.26822-2-tzimmermann@suse.de
2020-11-24 09:10:21 +01:00

420 lines
9.0 KiB
C

// SPDX-License-Identifier: GPL-2.0 OR MIT
/* Copyright 2017-2019 Qiang Yu <yuq825@gmail.com> */
#include <linux/mm.h>
#include <linux/sync_file.h>
#include <linux/pagemap.h>
#include <linux/shmem_fs.h>
#include <linux/dma-mapping.h>
#include <drm/drm_file.h>
#include <drm/drm_syncobj.h>
#include <drm/drm_utils.h>
#include <drm/lima_drm.h>
#include "lima_drv.h"
#include "lima_gem.h"
#include "lima_vm.h"
int lima_heap_alloc(struct lima_bo *bo, struct lima_vm *vm)
{
struct page **pages;
struct address_space *mapping = bo->base.base.filp->f_mapping;
struct device *dev = bo->base.base.dev->dev;
size_t old_size = bo->heap_size;
size_t new_size = bo->heap_size ? bo->heap_size * 2 :
(lima_heap_init_nr_pages << PAGE_SHIFT);
struct sg_table sgt;
int i, ret;
if (bo->heap_size >= bo->base.base.size)
return -ENOSPC;
new_size = min(new_size, bo->base.base.size);
mutex_lock(&bo->base.pages_lock);
if (bo->base.pages) {
pages = bo->base.pages;
} else {
pages = kvmalloc_array(bo->base.base.size >> PAGE_SHIFT,
sizeof(*pages), GFP_KERNEL | __GFP_ZERO);
if (!pages) {
mutex_unlock(&bo->base.pages_lock);
return -ENOMEM;
}
bo->base.pages = pages;
bo->base.pages_use_count = 1;
mapping_set_unevictable(mapping);
}
for (i = old_size >> PAGE_SHIFT; i < new_size >> PAGE_SHIFT; i++) {
struct page *page = shmem_read_mapping_page(mapping, i);
if (IS_ERR(page)) {
mutex_unlock(&bo->base.pages_lock);
return PTR_ERR(page);
}
pages[i] = page;
}
mutex_unlock(&bo->base.pages_lock);
ret = sg_alloc_table_from_pages(&sgt, pages, i, 0,
new_size, GFP_KERNEL);
if (ret)
return ret;
if (bo->base.sgt) {
dma_unmap_sgtable(dev, bo->base.sgt, DMA_BIDIRECTIONAL, 0);
sg_free_table(bo->base.sgt);
} else {
bo->base.sgt = kmalloc(sizeof(*bo->base.sgt), GFP_KERNEL);
if (!bo->base.sgt) {
sg_free_table(&sgt);
return -ENOMEM;
}
}
ret = dma_map_sgtable(dev, &sgt, DMA_BIDIRECTIONAL, 0);
if (ret) {
sg_free_table(&sgt);
kfree(bo->base.sgt);
bo->base.sgt = NULL;
return ret;
}
*bo->base.sgt = sgt;
if (vm) {
ret = lima_vm_map_bo(vm, bo, old_size >> PAGE_SHIFT);
if (ret)
return ret;
}
bo->heap_size = new_size;
return 0;
}
int lima_gem_create_handle(struct drm_device *dev, struct drm_file *file,
u32 size, u32 flags, u32 *handle)
{
int err;
gfp_t mask;
struct drm_gem_shmem_object *shmem;
struct drm_gem_object *obj;
struct lima_bo *bo;
bool is_heap = flags & LIMA_BO_FLAG_HEAP;
shmem = drm_gem_shmem_create(dev, size);
if (IS_ERR(shmem))
return PTR_ERR(shmem);
obj = &shmem->base;
/* Mali Utgard GPU can only support 32bit address space */
mask = mapping_gfp_mask(obj->filp->f_mapping);
mask &= ~__GFP_HIGHMEM;
mask |= __GFP_DMA32;
mapping_set_gfp_mask(obj->filp->f_mapping, mask);
if (is_heap) {
bo = to_lima_bo(obj);
err = lima_heap_alloc(bo, NULL);
if (err)
goto out;
} else {
struct sg_table *sgt = drm_gem_shmem_get_pages_sgt(obj);
if (IS_ERR(sgt)) {
err = PTR_ERR(sgt);
goto out;
}
}
err = drm_gem_handle_create(file, obj, handle);
out:
/* drop reference from allocate - handle holds it now */
drm_gem_object_put(obj);
return err;
}
static void lima_gem_free_object(struct drm_gem_object *obj)
{
struct lima_bo *bo = to_lima_bo(obj);
if (!list_empty(&bo->va))
dev_err(obj->dev->dev, "lima gem free bo still has va\n");
drm_gem_shmem_free_object(obj);
}
static int lima_gem_object_open(struct drm_gem_object *obj, struct drm_file *file)
{
struct lima_bo *bo = to_lima_bo(obj);
struct lima_drm_priv *priv = to_lima_drm_priv(file);
struct lima_vm *vm = priv->vm;
return lima_vm_bo_add(vm, bo, true);
}
static void lima_gem_object_close(struct drm_gem_object *obj, struct drm_file *file)
{
struct lima_bo *bo = to_lima_bo(obj);
struct lima_drm_priv *priv = to_lima_drm_priv(file);
struct lima_vm *vm = priv->vm;
lima_vm_bo_del(vm, bo);
}
static int lima_gem_pin(struct drm_gem_object *obj)
{
struct lima_bo *bo = to_lima_bo(obj);
if (bo->heap_size)
return -EINVAL;
return drm_gem_shmem_pin(obj);
}
static int lima_gem_vmap(struct drm_gem_object *obj, struct dma_buf_map *map)
{
struct lima_bo *bo = to_lima_bo(obj);
if (bo->heap_size)
return -EINVAL;
return drm_gem_shmem_vmap(obj, map);
}
static int lima_gem_mmap(struct drm_gem_object *obj, struct vm_area_struct *vma)
{
struct lima_bo *bo = to_lima_bo(obj);
if (bo->heap_size)
return -EINVAL;
return drm_gem_shmem_mmap(obj, vma);
}
static const struct drm_gem_object_funcs lima_gem_funcs = {
.free = lima_gem_free_object,
.open = lima_gem_object_open,
.close = lima_gem_object_close,
.print_info = drm_gem_shmem_print_info,
.pin = lima_gem_pin,
.unpin = drm_gem_shmem_unpin,
.get_sg_table = drm_gem_shmem_get_sg_table,
.vmap = lima_gem_vmap,
.vunmap = drm_gem_shmem_vunmap,
.mmap = lima_gem_mmap,
};
struct drm_gem_object *lima_gem_create_object(struct drm_device *dev, size_t size)
{
struct lima_bo *bo;
bo = kzalloc(sizeof(*bo), GFP_KERNEL);
if (!bo)
return NULL;
mutex_init(&bo->lock);
INIT_LIST_HEAD(&bo->va);
bo->base.map_wc = true;
bo->base.base.funcs = &lima_gem_funcs;
return &bo->base.base;
}
int lima_gem_get_info(struct drm_file *file, u32 handle, u32 *va, u64 *offset)
{
struct drm_gem_object *obj;
struct lima_bo *bo;
struct lima_drm_priv *priv = to_lima_drm_priv(file);
struct lima_vm *vm = priv->vm;
obj = drm_gem_object_lookup(file, handle);
if (!obj)
return -ENOENT;
bo = to_lima_bo(obj);
*va = lima_vm_get_va(vm, bo);
*offset = drm_vma_node_offset_addr(&obj->vma_node);
drm_gem_object_put(obj);
return 0;
}
static int lima_gem_sync_bo(struct lima_sched_task *task, struct lima_bo *bo,
bool write, bool explicit)
{
int err = 0;
if (!write) {
err = dma_resv_reserve_shared(lima_bo_resv(bo), 1);
if (err)
return err;
}
/* explicit sync use user passed dep fence */
if (explicit)
return 0;
return drm_gem_fence_array_add_implicit(&task->deps, &bo->base.base, write);
}
static int lima_gem_add_deps(struct drm_file *file, struct lima_submit *submit)
{
int i, err;
for (i = 0; i < ARRAY_SIZE(submit->in_sync); i++) {
struct dma_fence *fence = NULL;
if (!submit->in_sync[i])
continue;
err = drm_syncobj_find_fence(file, submit->in_sync[i],
0, 0, &fence);
if (err)
return err;
err = drm_gem_fence_array_add(&submit->task->deps, fence);
if (err) {
dma_fence_put(fence);
return err;
}
}
return 0;
}
int lima_gem_submit(struct drm_file *file, struct lima_submit *submit)
{
int i, err = 0;
struct ww_acquire_ctx ctx;
struct lima_drm_priv *priv = to_lima_drm_priv(file);
struct lima_vm *vm = priv->vm;
struct drm_syncobj *out_sync = NULL;
struct dma_fence *fence;
struct lima_bo **bos = submit->lbos;
if (submit->out_sync) {
out_sync = drm_syncobj_find(file, submit->out_sync);
if (!out_sync)
return -ENOENT;
}
for (i = 0; i < submit->nr_bos; i++) {
struct drm_gem_object *obj;
struct lima_bo *bo;
obj = drm_gem_object_lookup(file, submit->bos[i].handle);
if (!obj) {
err = -ENOENT;
goto err_out0;
}
bo = to_lima_bo(obj);
/* increase refcnt of gpu va map to prevent unmapped when executing,
* will be decreased when task done
*/
err = lima_vm_bo_add(vm, bo, false);
if (err) {
drm_gem_object_put(obj);
goto err_out0;
}
bos[i] = bo;
}
err = drm_gem_lock_reservations((struct drm_gem_object **)bos,
submit->nr_bos, &ctx);
if (err)
goto err_out0;
err = lima_sched_task_init(
submit->task, submit->ctx->context + submit->pipe,
bos, submit->nr_bos, vm);
if (err)
goto err_out1;
err = lima_gem_add_deps(file, submit);
if (err)
goto err_out2;
for (i = 0; i < submit->nr_bos; i++) {
err = lima_gem_sync_bo(
submit->task, bos[i],
submit->bos[i].flags & LIMA_SUBMIT_BO_WRITE,
submit->flags & LIMA_SUBMIT_FLAG_EXPLICIT_FENCE);
if (err)
goto err_out2;
}
fence = lima_sched_context_queue_task(
submit->ctx->context + submit->pipe, submit->task);
for (i = 0; i < submit->nr_bos; i++) {
if (submit->bos[i].flags & LIMA_SUBMIT_BO_WRITE)
dma_resv_add_excl_fence(lima_bo_resv(bos[i]), fence);
else
dma_resv_add_shared_fence(lima_bo_resv(bos[i]), fence);
}
drm_gem_unlock_reservations((struct drm_gem_object **)bos,
submit->nr_bos, &ctx);
for (i = 0; i < submit->nr_bos; i++)
drm_gem_object_put(&bos[i]->base.base);
if (out_sync) {
drm_syncobj_replace_fence(out_sync, fence);
drm_syncobj_put(out_sync);
}
dma_fence_put(fence);
return 0;
err_out2:
lima_sched_task_fini(submit->task);
err_out1:
drm_gem_unlock_reservations((struct drm_gem_object **)bos,
submit->nr_bos, &ctx);
err_out0:
for (i = 0; i < submit->nr_bos; i++) {
if (!bos[i])
break;
lima_vm_bo_del(vm, bos[i]);
drm_gem_object_put(&bos[i]->base.base);
}
if (out_sync)
drm_syncobj_put(out_sync);
return err;
}
int lima_gem_wait(struct drm_file *file, u32 handle, u32 op, s64 timeout_ns)
{
bool write = op & LIMA_GEM_WAIT_WRITE;
long ret, timeout;
if (!op)
return 0;
timeout = drm_timeout_abs_to_jiffies(timeout_ns);
ret = drm_gem_dma_resv_wait(file, handle, write, timeout);
if (ret == -ETIME)
ret = timeout ? -ETIMEDOUT : -EBUSY;
return ret;
}